Researchers gave personality tests to 235 subjects—from teens to people in their 60s. Those subjects also rated how aggressive they considered different breeds of dogs to be, from cocker spaniels to pit bulls, and chose which type they'd most like to own.

As the authors expected, the most unfriendly study volunteers, and the youngest, preferred the meanest breeds. But the stereotyping ends there. Pit bull lovers weren't any more likely to have delinquent past behavior—like carrying weapons for fights—than people who preferred friendly Labs.

In fact, pit bull lovers actually scored higher for conscientiousness on the personality test. Which means they may be more rule-oriented, careful and organized—the perfect candidates for dog training classes, the authors say. So next time you see someone walking a fearsome dog, that person’s bark may be worse than his bite.

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